A liquid crystal display device includes a lower substrate including a color filter including a light blocking layer, a lower substrate on which an ITO pixel electrode is formed; an active circuit portion including a liquid crystal layer, a thin film transistor, and a capacitor layer; and an upper substrate on which an ITO pixel electrode is formed. The light blocking layer blocks uncontrolled light transmitted out of a transparent pixel electrode of a substrate and thus prevents contrast reduction due to light transmitted through a thin film transistor. Red, green, and blue light blocking layers transmit light with a predetermined wavelength of white light and display colors.
The light blocking layer is generally manufactured by a pigment dispersion method. The pigment dispersion method includes coating a transparent substrate with a colorant-containing photopolymerizable composition, exposing to provide a pattern by thermal curing, and removing non-exposed portions with a solvent.
However, when a photosensitive polyimide or phenol-based resin is used as a binder resin in the pigment dispersion method, high heat resistance may be obtained but sensitivity can be lowered and an organic solvent is required as a development solvent. A photoresist using an azide compound can have low sensitivity and heat resistance and may be affected by oxygen during exposure. Also, an acrylic-based resin can have good heat resistance, shrinkage-resistance, chemical resistance, and the like, but reduced sensitivity, developability, and close-contacting (adhesive) properties.
In addition, since black pigments are included in a large amount in order to adjust optical density of a light blocking layer, sensitivity, developability, and close-contacting properties may significantly deteriorate.